The success or failure of seeding operations depends on a combination of environmental and practice factors including a sound choice of seeding location, seeding timing and soil preparation. In addition to the above obvious factors a substantial contribution to the likely success of seeding operations is governed by the precision and accuracy with which seed is deposited in the ground. These factors have to date been limited by the availability of precision seeding devices including the limited ability of current technology to provide for sowing at an accurate and precise depth over a range of terrain. A further limitation of current technology involves the careful control of soil during furrow formation and during seed deposition through to closing of the furrow after the seed has been deposited.
To date the generic form of seeding device includes a pivoted arm onto which is located a coulter disc for forming a furrow followed by a packer wheel which doubles as a height adjustment means. The primitive form of the currently available mechanisms results in the arcuate movement of the coulter and packer wheel which causes inaccuracies of seeding depth as the mechanism traverses undulations in the soil or earth surface.
In order to overcome these inaccuracies, improved seeding devices have been developed which incorporate mounting means adapted for accurate vertical travel of seeding mechanism by way of a parallel hinged bracket such that vertical movement of the coulter disc and packer wheel faithfully follow undulations in the soil and maintain an accuracy of seeding depth notwithstanding variations in the soil contour.
Such mechanisms provide vastly Improved seeding performance over the existing prior art. However, limitations still exist with respect to the actual formation of the furrow which often fails due to collapse, unwanted displacement and undesirable compaction during seed placement. Accordingly such seeding devices can be further Improved with the provision of additional mechanisms to improve the accuracy of furrow preparation immediately prior to seed deposition and subsequent packing following seed deposition.